Hub gear

ABSTRACT

A multi-speed hub gear, comprising: an axle adapted to be fixed against rotation; a hub shell; a plurality of planetary gear sets, each comprising: a central gear concentrically fixed on the axle, a rotating gear carrier mounting at least one rotating gear to revolve around the center of the central gear; and a ring gear rotated by the at least one rotating gear; wherein a respective the ring gear of one of the sets is mechanically connected to a respective the rotating gear carrier of another of the sets such that the sets rotate in conjunction; and a gear shifter adapted to engage at least one of the sets to the hub shell while disengaging another of the sets from the hub shell.

RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.15/479,412 filed on Apr. 5, 2017, which claims the benefit of priorityunder 35 USC § 119(e) of U.S. Provisional Patent Application No.62/318,347 filed on Apr. 5, 2016, the contents of which are incorporatedherein by reference in their entirety.

FIELD AND BACKGROUND OF THE INVENTION

The present invention, in some embodiments thereof, relates to a hubgear and, more particularly, but not exclusively, to a multi-speed hubgear where the transmission ratio is changed by engaging one planetarygear set while disengaging another planetary gear set rotating inconjunction.

A conventional speed-changing transmission hub uses a planetary geartrain comprising ring gears, rotating gears and central gears. Torque isinputted to the planetary gear train either via the ring gear or thecarrier of the rotating gears, as controlled by a clutch, which engageseither with the ring gear or with the carrier, thus controlling the pathof torque within the planetary gear train and the degrees of freedom ofthe sun gears for various speeds.

SUMMARY OF THE INVENTION

According to an aspect of some embodiments of the present inventionthere is provided a multi-speed hub gear, comprising: an axle adapted tobe fixed against rotation; a hub shell; a plurality of planetary gearsets, each comprising: a central gear concentrically fixed on the axle;a rotating gear carrier mounting at least one rotating gear to revolvearound the center of the central gear; and a ring gear rotated by the atleast one rotating gear; wherein a respective the ring gear of one ofthe plurality of planetary gear sets is mechanically connected to arespective the rotating gear carrier of another of the plurality ofplanetary gear sets such that the plurality of planetary gear setsrotate in conjunction; and a gear shifter adapted to engage at least oneof the plurality of planetary gear sets to the hub shell whiledisengaging another of the plurality of planetary gear sets from the hubshell. Each planetary gear set is rotating at a different speed, so thisallows shifting gears under load, by transferring the load to aplanetary gear set which is rotating at a correct speed.

Optionally, the gear shifter includes at least one linear actuatorhaving a motion axis parallel to the axle and the engaging anddisengaging of the plurality of planetary gear sets from the hub shellis done by a linear motion of the at least one linear actuator along themotion axis.

More optionally, the at least one linear actuator includes a pluralityof non-linear slits, each laterally positioning a pin in a position ofwhere the pin is engaging one of the planet carriers to the hub shelland in a position of where the pin is disengaging the one of the planetcarriers from the hub shell.

Optionally, the engaging and disengaging includes simultaneouslydisengaging a planet carrier of one of the plurality of planetary gearsets and engaging a planet carrier of a next one of the plurality ofplanetary gear sets.

Optionally, the plurality of planetary gear sets have the sametransmission ratio.

Optionally, the plurality of planetary gear sets are having differenttransmission ratios.

Optionally, the engaging and disengaging further includes partlydisengaging at least one of the plurality of planetary gear sets so theat least one of the plurality of planetary gear sets rotates freely at alower speed relative to the hub shell.

Optionally, the multi-speed hub gear further comprises a plurality oflockable bearings, each concentrically mounted between one of the ringgears and the hub shell; wherein the engaging and disengaging is done bychanging position of at least one of the plurality of lockable bearingsbetween a locked position where a plurality of rollers of the lockablebearing are locked and an unlocked position where the plurality ofrollers are not locked and are free to rotate.

More optionally, the engaging and disengaging further includes partlyengaging at least one of the plurality of planetary gear sets bychanging position at least one of the plurality of lockable bearings toa partly unlocked position where a plurality of rollers of the lockablebearing are allowed to be locked by the outer one-way ring and thelockable bearing operates as a one-way bearing.

More optionally, each of the plurality of lockable bearings includes anouter one-way ring and two ring cage plates which includes a pluralityof depressions loosely holding the plurality of rollers between the tworing cage plates; wherein the ring cage plates rotate relative to theone-way ring and moves the plurality of rollers between the lockedposition where the plurality of rollers are locked by the outer one-wayring, and the unlocked position wherein the plurality of rollers are notlocked by the outer one-way ring.

More optionally, each of the plurality of rollers is pushed into lockedposition by a spring against angled surface of the outer one-way ring.

More optionally, the two ring cage plates are rotated by a pin fixed toone of the two ring cage plates, the pin is laterally shifted todifferent positions by the at least one linear actuator.

Optionally, the gear shifter is activated by a governor according to aturning speed of the hub shell.

More optionally, the governor includes a drive plate which pushes thegear shifter when turning speed of the governor increases.

More optionally, the governor includes a return spring which pulls thedrive plate to an initial position when turning speed of the governordecreases

More optionally, the governor includes at least one counterweight havingan initial position close to the axle, the at least one counterweight ispushed away from the axle by centrifugal force applied when turningspeed of the governor increases.

More optionally, the at least one counterweight pushes a drive platewhich pushes the gear shifter when turning speed of the governorincreases.

More optionally, the at least one counterweight pushes at least onepushing flap mechanically connected to the at least one counterweight,the at least one pushing flap pushes a drive plate which pushes the gearshifter when turning speed of the governor increases.

More optionally, the governor includes a governor planetary gear set,the governor planetary gear set comprising: a governor rotating gearcarrier fixed on the axle and mounting at least one governor rotatinggear; a governor ring gear concentrically fixed to the hub shell; and agovernor central gear mechanically connected to a governor base so thegovernor base turns faster than the hub shell.

More optionally, the governor includes at least one speed sensor and atleast one motor electronically connected to the at least one speedsensor and activates the gear shifter.

Optionally, the multi-speed hub gear further comprises: a double one-waybearing mechanism which drives the hub shell.

More optionally, the double one-way bearing mechanism includes: a firstone-way bearing connecting a sprocket to a first rotating gear carrierof a first of the plurality of planetary gear sets so the sprocketdrives the first planetary gear set; and a second one-way bearingconnecting the first rotating gear carrier to the hub shell, so sprocketalso drives the hub shell.

More optionally, the at least one of the first one-way bearing and thesecond one-way bearing includes a trapped roller mechanism.

More optionally, the at least one of the first one-way bearing and thesecond one-way bearing includes a sprag clutch mechanism.

More optionally, the at least one of the first one-way bearing and thesecond one-way bearing includes a ratchet mechanism.

Optionally, the multi-speed hub gear is used in a wheeled vehicle,wherein the axle is adapted to be fixed against rotation in a wheelholder of a wheeled vehicle frame and the hub shell is mechanicallyconnected to a wheel.

According to an aspect of some embodiments of the present inventionthere is provided a method of changing transmission ratio in amulti-speed hub gear, comprising: monitoring turning speed of a hubshell of the multi-speed hub gear relative to an axle adapted to befixed against rotation; shifting a gear shifter according to themonitored speed; engaging at least one of a plurality of planetary gearsets to the hub shell, each of the plurality of planetary gear setscomprising: a central gear concentrically fixed on the axle; a rotatinggear carrier mounting at least one rotating gear to revolve around thecenter of the central gear; and a ring gear rotated by the at least onerotating gear; wherein a respective the ring gear of one of theplurality of planetary gear sets is mechanically connected to arespective the rotating gear carrier of another of the plurality ofplanetary gear sets such that the plurality of planetary gear setsrotate in conjunction; and disengaging another one of the plurality ofplanetary gear sets from the hub shell.

According to an aspect of some embodiments of the present inventionthere is provided a multi-speed hub gear, comprising: an axle adapted tobe fixed against rotation; a hub shell; a plurality of planetary gearsets, each comprising: a central gear concentrically fixed on the axle;a rotating gear carrier mounting at least one rotating gear to revolvearound the center of the central gear; and a ring gear rotated by the atleast one rotating gear; and a gear shifter adapted to engage at leastone of the plurality of planetary gear sets to the hub shell whiledisengaging another of the plurality of planetary gear sets from the hubshell; wherein the gear shifter includes at least one linear actuatorhaving a motion axis parallel to the axle and the engaging anddisengaging of the plurality of planetary gear sets from the hub shellis done by a linear motion of the at least one linear actuator along themotion axis.

According to an aspect of some embodiments of the present inventionthere is provided a multi-speed hub gear, comprising: an axle adapted tobe fixed against rotation; a hub shell; a plurality of planetary gearsets, each comprising: a central gear concentrically fixed on the axle;a rotating gear carrier mounting at least one rotating gear to revolvearound the center of the central gear; and a ring gear rotated by the atleast one rotating gear; and a plurality of lockable bearings, eachconcentrically mounted between one of the planet carriers and the hubshell; wherein the engaging and disengaging is done by changing positionof at least one of the plurality of lockable bearings between a lockedposition where a plurality of rollers of the lockable bearing are lockedand an unlocked position where the plurality of rollers are not lockedand are free to rotate.

According to an aspect of some embodiments of the present inventionthere is provided a multi-speed hub gear, comprising: an axle adapted tobe fixed against rotation; a hub shell; a plurality of planetary gearsets, each comprising: a central gear concentrically fixed on the axle;a rotating gear carrier mounting at least one rotating gear to revolvearound the center of the central gear; and a ring gear rotated by the atleast one rotating gear; a gear shifter adapted to engage at least oneof the plurality of planetary gear sets to the hub shell whiledisengaging another of the plurality of planetary gear sets from the hubshell; and a governor monitoring a turning speed of the hub shell andactivating the gear shifter according to the turning speed.

Unless otherwise defined, all technical and/or scientific terms usedherein have the same meaning as commonly understood by one of ordinaryskill in the art to which the invention pertains. Although methods andmaterials similar or equivalent to those described herein can be used inthe practice or testing of embodiments of the invention, exemplarymethods and/or materials are described below. In case of conflict, thepatent specification, including definitions, will control. In addition,the materials, methods, and examples are illustrative only and are notintended to be necessarily limiting.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

Some embodiments of the invention are herein described, by way ofexample only, with reference to the accompanying drawings. With specificreference now to the drawings in detail, it is stressed that theparticulars shown are by way of example and for purposes of illustrativediscussion of embodiments of the invention. In this regard, thedescription taken with the drawings makes apparent to those skilled inthe art how embodiments of the invention may be practiced.

In the drawings:

FIG. 1 is an illustration of a multi-speed hub gear for a wheeledvehicle, according to some embodiments of the present invention;

FIGS. 2A and 2B are cross-section illustrations of the multi-speed hubgear of FIG. 1, according to some embodiments of the present invention;

FIG. 3A and 3B are a cross-section illustration of a double one-waybearing mechanism of the multi-speed hub gear of FIG. 1 and a magnifiedview thereof, respectively, according to some embodiments of the presentinvention;

FIG. 4 is an illustration of the multi-speed hub gear of FIG. 1 whereinthe planetary gear sets are visible, according to some embodiments ofthe present invention;

FIG. 5A and 5B are a cross-section illustration of the first planetarygear set of the multi-speed hub gear of FIG. 1 and a magnified viewthereof, respectively, according to some embodiments of the presentinvention;

FIG. 6 is an illustration of two ring cage plates of a lockable bearingholding rollers, according to some embodiments of the present invention;

FIG. 7 is an illustration of ring cage plates with spring loadedrollers, according to some embodiments of the present invention;

FIG. 8 is an illustration of the multi-speed hub gear of FIG. 1 whereinthe linear actuators are visible, according to some embodiments of thepresent invention;

FIG. 9A, 9B, 9C and 9D are illustrations of a side view of an exemplaryposition of the linear actuators and section views of the planetary gearsets, respectively, according to some embodiments of the presentinvention;

FIGS. 10A, 10B, 10C and 10D are illustrations of a side view ofdifferent positions of the linear actuators, according to someembodiments of the present invention;

FIG. 11A and FIG. 11B are illustrations of the governor of themulti-speed hub gear of FIG. 1 in low speed and FIG. 11C and FIG. 11Dare illustrations of the governor in high speed, according to someembodiments of the present invention;

FIG. 12 is an illustration of the governor of the multi-speed hub gearof FIG. 1 having a load adjustment mechanism, according to someembodiments of the present invention;

FIG. 13 is an illustration of the governor of the multi-speed hub gearof FIG. 1 having a planetary gear set, according to some embodiments ofthe present invention;

FIG. 14A, FIG. 14B and FIG. 14C are illustrations of a governor of amulti-speed hub gear, having weighted bearings that are directly pushingthe drive plate, according to some embodiments of the present invention;

FIG. 15A is an illustration of a cross section of the governor of FIG.14C at low speed, according to some embodiments of the presentinvention;

FIG. 15B is an illustration of a cross section of the governor of FIG.14C at high speed, according to some embodiments of the presentinvention;

FIG. 16 is a schematic illustration of an electromechanical governor ina multi-speed hub gear, according to some embodiments of the presentinvention;

FIG. 17 is a schematic illustration of a multi-speed hub gear, accordingto some embodiments of the present invention; and

FIG. 18 is a flowchart schematically representing a method for changingtransmission ratio in a multi-speed hub gear, according to someembodiments of the present invention.

DESCRIPTION OF SPECIFIC EMBODIMENTS OF THE INVENTION

The present invention, in some embodiments thereof, relates to a hubgear and, more particularly, but not exclusively, to a multi-speed hubgear where the transmission ratio is changed by engaging one planetarygear set while disengaging another planetary gear set rotating inconjunction.

According to some embodiments of the present invention, there isprovided a multi-speed hub gear. The multi-speed hub gear may be usedfor a wheeled vehicle, for example a bicycle or a tricycle operated bypedaling or by an electric engine. The multi-speed hub gear may also beused for water or wind turbines, locking mechanisms, productionmachinery and/or any other use requiring a small efficient automaticgear. The multi-speed hub gear includes multiple planetary gear sets andoptionally a gear shifting mechanism for converting force, such as acentrifugal force, to a gear shifter action. The planetary gear sets areconnected to each other and rotate in conjunction, each at a differentspeed (each planetary gear set rotates faster than its predecessor). Thegear shifting mechanism transfers the load from one planetary gear setto another by engaging it to the hub shell.

Optionally, each of the planetary gear sets includes a central gearconcentrically fixed on an axle of the hub gear, a rotating gear carriermounting rotating gears, for example two or three, and a ring gearrotated by the rotating gears. Optionally, all planetary gear sets arearranged to rotate in conjunction, with a ratio between them. Forexample, a ring gear of one of the planetary gear sets is mechanicallyconnected a rotating gear carrier of another of the planetary gear sets.When the turning speed of the hub gear increases, the gear shifter, forexample one or more linear actuators having a motion axis parallel tothe axle, engage one or more of the planetary gear sets to the hub shellof the hub gear while disengaging another planetary gear set from thehub shell. Optionally, the gear shifter is operated based on centrifugalforce.

Optionally, for the initial speed, none of the planetary gear sets isengaged, and a sprocket drives the hub shell directly, optionally via adouble one-way bearing mechanism which also drives the first planetarygear set.

For the higher speeds, the planetary gear sets are alternately engagedand drive the hub shell. Optionally, each of the planetary gear sets isconnected to the hub shell via a lockable bearing concentrically mountedbetween the planetary gear set and the hub shell. Each lockable bearinghas a locked position, where rollers of the lockable bearing are lockedso the planetary gear set drives the hub shell, and an unlocked positionwhere the rollers of the lockable bearing are not locked and are free torotate so the planetary gear set does not drive the hub shell.Optionally, the lockable bearings are one-way bearings and planetarygear sets of lower speeds are only partially disengaged and are stillconnected to the hub shell but do not drive the hub shell.

Optionally, the monitoring of the turning speed of the hub gear and theshifting of the gear shifter is done by a governor mechanism. Thegovernor mechanism may include counterweights movable by centrifugalforce created by the turning speed of the hub gear, and a drive platepushed by the counterweights which shifts the gear shifter.

The multi-speed hub gear, according to some embodiments of the presentinvention, is a fully automatic internal hub gear, which may be shiftedup and down under load. Also, the hub gear may be used by both electricand non-electric wheeled vehicle, and shifting may be controlled bymanual shifters, electronic shifters and/or any other internal orexternal means.

Before explaining at least one embodiment of the invention in detail, itis to be understood that the invention is not necessarily limited in itsapplication to the details of construction and the arrangement of thecomponents and/or methods set forth in the following description and/orillustrated in the drawings and/or the Examples. The invention iscapable of other embodiments or of being practiced or carried out invarious ways.

Referring now to the drawings, FIG. 1 is an illustration of amulti-speed hub gear 100 for a wheeled vehicle, such as a bicycle whichincludes multiple planetary gear sets rotating in conjunction and a gearshifter adapted to engage one set to a hub shell while disengaginganother set, according to some embodiments of the present invention.Multi-speed hub gear 100 may be for example of a length 135 millimeters(to fit an Over Lockout Distance which is conventional in the bicycleindustry) and 105 millimeters in diameter. It may fit any wheeledvehicle frame that supports such length and a horizontal dropout.

Multi-speed hub gear 100 includes an axle 101 adapted to be fixedagainst rotation in a wheel holder of a wheeled vehicle frame, by amechanical connection of each end of axle 101. Multi-speed hub gear 100also includes a hub shell 102 having spoke mounts 103 for mechanicallyconnecting a plurality of spokes of a wheel. Hub shell 102 is concentricto axle 101 and rotates the wheel by applying force on the spokes. Hubshell 102 is rotated by a sprocket 104, which is concentrically mountedon axle 101, via the internal gear mechanism of the hub gear. Sprocket104 is driven by a chain that may be driven by pedals of the wheeledvehicle and/or a motor.

Reference is now made to FIGS. 2A and 2B, which are cross-sectionillustrations of multi-speed hub gear 100, according to some embodimentsof the present invention.

Hub gear 100 includes multiple planetary gear sets. The planetary gearsets may have the same transmission ratio or have different transmissionratios. According to some embodiments as shown in the drawings, hub gear100 includes three planetary gear sets 109, providing three differenttransmission ratios when operating. Optionally, hub gear 100 includesany number of planetary gear sets, for example, 4, 5, 10 or 12 planetarygear sets. Planetary gear sets 109 are positioned concentrically aroundaxle 101, one next to the other. Exemplary dimensions of hub gear 100may be, for example, a diameter of 127 millimeters and a length of 134millimeters.

When sprocket 104 is driven at different speeds, the transmission ratiobetween sprocket 104 and hub shell 102 is changed. For example,rotational speed may increase between 15% and 30% when shifting from oneplanetary gear set to another. The change of transmission ratio iscontrolled by a governor 106, by shifting a gear shifter that engagesone planetary gear set to a hub shell while disengaging anotherplanetary gear set. Optionally, the gear shifter includes linearactuators 107, having a motion axis parallel to axle 101 and move alongthe motion axis to engage and disengage planetary gear sets 109.Optionally, linear actuators 107 are rotated along with hub shell 102.

For the initial speed, none of planetary gear sets 109 is engaged, andsprocket 104 drives hub shell 102 directly, optionally via a doubleone-way bearing mechanism 108. For the second, third and fourth speeds,planetary gear sets 109 are alternately engaged and driving hub shell102.

Reference is now made to FIG. 3A and 3B, which are views of across-section illustration of a double one-way bearing mechanism 108 ofmulti-speed hub gear 100, according to some embodiments of the presentinvention. Sprocket 104 is mechanically connected to a sprocket sleeve110, which is also concentrically positioned around axle 101. An outersurface of sprocket sleeve 110 includes angled surfaces 111 that areacting as the inner part of a one-way bearing mechanism. The angle ofangled surfaces 111 may be, for example, 7 degrees.

The one-way bearing mechanism includes rollers 112 which are positionedbetween angled surfaces 111 of sprocket sleeve 110 and an inner surfaceof a wheel element, which is the first rotating gear carrier 113 of thefirst planetary gear set. The one-way bearing mechanism includes, forexample, 6, 18, 30 and/or any number of rollers, depending on thediameter of hub gear 100. When sprocket 104 and sprocket sleeve 110 arerotated faster than first rotating gear carrier 113, rollers 112 arepushed to a narrow space between angled surfaces 111 and first rotatinggear carrier 113, and sprocket sleeve 110 locks to first rotating gearcarrier 113 and turns it. When sprocket 104 and sprocket sleeve 110 arerotated slower or to the other direction than first rotating gearcarrier 113, rollers 112 are pushed to a wide space between angledsurfaces 111 and first rotating gear carrier 113, then rollers 112 arefree to rotate, allowing freewheel motion of sprocket sleeve 110.

An outer surface of first rotating gear carrier 113 also includes angledsurfaces, similar to angled surfaces 111, which are acting as the innerpart of a second one-way bearing mechanism. The second one-way bearingmechanism also includes rollers 114, located between first rotating gearcarrier 113 and hub shell 102. The second one-way bearing mechanismoperates in a similar way, so when first rotating gear carrier 113rotated faster than hub shell 102, rollers 114 are locked and firstrotating gear carrier 113 drives hub shell 102. Therefore, at the firstspeed of sprocket 104, sprocket sleeve 110 drives first rotating gearcarrier 113, which drives both hub shell 102 and the first planetarygear set.

Alternatively, other mechanisms may be used as alternatives to trappedrollers for each one-way bearing of double one-way bearing mechanism108, for example a sprag clutch and/or a ratchet mechanism.

Reference is now made to FIG. 4, which is an illustration of multi-speedhub gear 100 wherein planetary gear sets 109 are visible, according tosome embodiments of the present invention. Planetary gear sets 109include a first planetary gear set 115, a second planetary gear set 116and a third planetary gear set 117. Reference is also made to FIG. 5Aand 5B, which are views of a cross-section illustration of firstplanetary gear set 115 of multi-speed hub gear 100, according to someembodiments of the present invention. Second planetary gear set 116 andthird planetary gear set 117 are of similar structure.

First planetary gear set 115 includes a central gear 118 concentricallyfixed on axle 101, first rotating gear carrier 113 which mounts multiplerotating gears 119 that revolve around the center of central gear 118and a ring gear 120 rotated by rotating gears 119. Ring gear 120 ismechanically connected to a second rotating gear carrier 121 of secondplanetary gear set 116. In a similar way, a second ring gear of secondplanetary gear set 116 is mechanically connected to a third rotatinggear carrier of third planetary gear set 117. Therefore, planetary gearsets 109 are rotating in conjunction. Because each ring gear ismechanically connected to the next rotating gear carrier, the motion istransferred through the planetary gear sets, and each planetary gear setincreases the rotation speed of the next planetary gear set. Theincrease may be, for example, 10%, 25%, 20% and/or any other increase.

Optionally, each of planetary gear sets 109 is connected to hub shell102 via a lockable bearing concentrically mounted between the planetarygear set and hub shell 102. The outer surface of the rotating gearcarrier of each planetary gear set is operating as the inner surface ofeach lockable bearing. Each lockable bearing has a locked position,where the rollers of the lockable bearing are locked and an unlockedposition where the rollers of the lockable bearing are not locked andare free to rotate. The lockable bearing may include, for example, 6,18, 30 and/or any number of rollers, depending on the diameter of hubgear 100. Optionally, each lockable bearing has a partly unlockedposition, where the rollers of the lockable bearing are partly unlockedand the lockable bearing operates as a one-way bearing. When a lockablebearing is in a locked position, the respective planetary gear set isengaged, and the respective rotating gear carrier drives hub shell 102.

When a lockable bearing is in an unlocked position, the respectiveplanetary gear set is disengaged, and the respective rotating gearcarrier is rotating freely relative to hub shell 102. When a lockablebearing is in a partly unlocked position, the respective planetary gearset is partly engaged, so the lockable bearing operates in a similar wayto the first and second one-way bearings of double one-way bearingmechanism 108. When the respective planetary gear set is rotating fasterthan hub shell 102, the respective rotating gear carrier drives hubshell 102, and when hub shell 102 is rotating faster than the respectiveplanetary gear set, the respective rotating gear carrier is rotatingfreely relative to hub shell 102.

Optionally, each of the lockable bearings, for example the firstlockable bearing connecting first planetary gear set 115 to hub shell102, includes an outer one-way ring 122 and two ring cage plates 123.The inner surface of outer one-way ring 122 includes angled surfaces124, similar to angled surfaces 111. The angle of angled surfaces 124may be, for example, 7 degrees. Ring cage plates 123 include multipledepressions 125 loosely holding multiple rollers 126 between two ringcage plates 123. Reference is now made to FIG. 6, which is anillustration of two ring cage plates 123 of a lockable bearing holdingrollers 126, according to some embodiments of the present invention. Thediameter of depressions 125 is larger by a small amount from thediameter of rollers 126 so that rollers 126 are held loosely. Forexample, the diameter of depressions 125 is 6 millimeters and thediameter of rollers 126 is 5 millimeters.

When ring cage plates 123 are moved counterclockwise relative to outerone-way ring 122, rollers 126 are in locked position and are locked byouter one-way ring 122. In this position, first planetary gear set 115is engaged to hub shell 102. When ring cage plates 123 are movedclockwise relative to outer one-way ring 122, rollers 126 are inunlocked position and first planetary gear set 115 is disengaged fromhub shell 102. When ring cage plates 123 are moved slightly clockwiserelative to outer one-way ring 122, rollers 126 are in partly unlockedposition and first planetary gear set 115 is partly engaged to hub shell102, via a one-way bearing mechanism.

Optionally, rollers 126 are pushed by springs. Reference is now made toFIG. 7, which is an illustration of ring cage plates with spring loadedrollers, according to some embodiments of the present invention. Springs154 constantly pushes rollers 126 against the angled surface of outerone-way ring 122. The purpose is to ensure rollers 126 always reach thelocked position.

Optionally, two ring cage plates 123 are rotated by a pin 127 which isfixed to one ring cage plate 123. Pin 127 is laterally shifted todifferent positions by one of linear actuators 107.

Reference is now made to FIG. 8, which is an illustration of multi-speedhub gear 100 wherein linear actuators 107 are visible, according to someembodiments of the present invention. Linear actuators 107 may includeone, two, four or any number of linear actuators. Optionally, similarlinear actuators are positioned on opposite sides of hub shell 102, sothe mechanism is balanced during operation. Linear actuators 107 aremoved by a drive plate 128 of governor 106 by pushing and pulling alongthe motion axis of linear actuators 107. Linear actuators 107 areadjacent to hub shell 102 and are rotated with hub shell 102 around axle101. Linear actuators 107 includes non-linear slits 129, each laterallypositioning a pin between a position of where the pin is engaging one ofplanetary gear sets 109 to hub shell 102 and a position of where the pinis disengaging the same one of planetary gear sets 109 from hub shell102.

Reference is now made to FIGS. 9A, 9B, 9C and 9D, which areillustrations of side views of an exemplary position of linear actuators107, according to some embodiments of the present invention. Theposition of linear actuators 107 is shown on 901. In this example,linear actuators 107 are positioned so pin 127 of first planetary gearset 115 is positioned in a middle position by a slit 129, so ring cageplates 123 are moved slightly clockwise relative to outer one-way ring122, as shown in 902. Optionally as shown in this example, in thisposition, first planetary gear set 115 is partly engaged. The second pinof second planetary gear set 116 is positioned in a leftward position bya slit 129, as shown in 903, so the second ring cage plates are movedcounterclockwise relative to the second outer one-way ring and secondplanetary gear set 116 is engaged to hub shell 102. The third pin ofthird planetary gear set 117 is positioned in a rightward position by aslit 129, as shown in 904, so the third ring cage plates are movedclockwise relative to the third outer one-way ring and third planetarygear set 117 is disengaged from hub shell 102.

Reference is now made to FIGS. 10A, 10B, 10C and 10D, which areillustrations of a side view of different positions of linear actuators107, according to some embodiments of the present invention. For eachspeed of hub gear 100, a next planetary gear set is engaged, the onebefore it is left partly engaged, and the rest of the planetary gearsets are disengaged. Leaving the last planetary gear set partly engagedhelps in reducing friction and noise of gear hub 100 during operation.

FIG. 10A shows the position of linear actuators 107 for the first speedof hub gear 100. In this position, all pins are at a rightward positionso planetary gear sets 109 are all disengaged and sprocket 104 driveshub shell 102 directly.

FIG. 10B shows the position of linear actuators 107 for the second speedof hub gear 100. In this position, pin 127 is in a leftward position sofirst planetary gear set 115 is engaged and drives hub shell 102, whilethe other planetary gear sets are disengaged.

FIG. 10C shows the position of linear actuators 107 for the third speedof hub gear 100. In this position, the second pin is in a leftwardposition so second planetary gear set 116 is engaged and drives hubshell 102. Pin 127 is in a middle position so first planetary gear set115 is partly engaged, and it only drives hub shell 102 when hub shell102 is rotated in a slower speed than ring gear 120.

FIG. 10D shows the position of linear actuators 107 for the fourth speedof hub gear 100. In this position, the third pin is in a leftwardposition so third planetary gear set 117 is engaged and drives hub shell102. The second pin is in a middle position so second planetary gear set116 is partly engaged and Pin 127 is in a middle position so firstplanetary gear set 115 is partly engaged.

Reference is now made to FIG. 11A and FIG. 11B, which are illustrationsof a governor 106 of multi-speed hub gear 100 in low speed and to 11Cand FIG. 11D, which are illustrations of a governor 106 in high speed,according to some embodiments of the present invention. Governor 106activates linear actuators 107 according to a turning speed of hub shell102, monitored by governor 106.

Optionally, the monitoring of the turning speed of hub shell 102 is doneby the centrifugal force created by the turning.

Optionally, governor 106 includes counterweights 135 that may moveoutward from axle 101 to hub shell 102 in response to centrifugal force.Governor 106 may include one, two, four or any number of counterweights135. Optionally, similar counterweights are positioned on opposite sidesof governor 106, so the mechanism is balanced during operation. As shownin FIG. 11A and FIG. 11B, at none or low speeds, counterweights 135 arepositioned close to axle 101. When the turning speed is increased,centrifugal force is created and pushes counterweights 135 outward fromaxle 101 to hub shell 102, as shown in FIG. 11C and FIG. 11D.

Optionally, counterweights 135 are mechanically connected to weightedbearings 136, which are moved outward along with counterweights 135 whenthe speed increases. Weighted bearings 136 are pushing flaps 137 whichare then pushing drive plate 128 along the axis of axle 101.

Optionally, governor 106 includes springs 138 which are mechanicallyconnected to pushing flaps 137 and to governor base 134. Springs 138create discrete positions for pushing flaps 137 and therefore creatediscrete positions for drive plate 128. The discrete positions arecorresponding to the positions of the slits of linear actuators 107.

Optionally, governor 106 includes a pre-load adjustment mechanism foradjusting the initial tension of pushing flaps 137. Reference is nowmade to FIG. 12, which is an illustration of governor 106 of multi-speedhub gear 100 having a pre-load adjustment mechanism, according to someembodiments of the present invention. The pre-load adjustment mechanismincludes an adjustment spring 139, which is a tension springmechanically connected to pushing flaps 137 and to an adjustable springholder 140. Spring holder 140 is mounted on a bearing 141 which acts asa bridge between the speed of the spring holder 140, moving withgovernor 106 and the speed of axle 101. The tension of adjustment spring139 keeps pushing flaps 137 closed and keeps drive plate 128 in aninitial position. Optionally, the amount of tension of adjustment spring139 is determined by the position of spring holder 140 and is controlledby an adjustment screw 142, which pushes and pulls adjustment spring139. Optionally, adjustment screw 142 is connected to spring holder 140and/or bearing 141 via mechanical elements such as an adjustment tube143, an adjustment pin 144 inserted into a slot 145 of axle 101 and/oran adjuster nut 146, all turning in the same speed as axle 101.

Optionally, governor 106 includes a governor planetary gear set.Reference is now made to FIG. 13, which is an illustration of governor106 of multi-speed hub gear 100 having a planetary gear set, accordingto some embodiments of the present invention. The governor planetarygear set includes a governor central gear 130 concentrically rotatesabout axle 101, a governor ring gear 131 concentrically fixed to hubshell 102 and a governor rotating gear carrier 132 fixed to axle 101 andmounting governor rotating gears 133. Governor central gear 130 ismechanically connected to governor base 134 so governor base 134, andtherefore governor 106, is driven by governor central gear 130 and turnsfaster than hub shell 102, in the opposite direction, according to thetransmission ratio of the governor planetary gear set. The fasterturning of governor 106 creates larger centrifugal force and thereforeincreases the accuracy of the monitoring of the turning speed. Also, asgovernor 106 is turning in an opposite direction than hub shell 102, ithelp in canceling gyroscopic forces and increase the stability of thevehicle.

Optionally, the weighted bearings are directly pushing the drive plate.Reference is now made to FIG. 14A, FIG. 14B and FIG. 14C, which areillustrations of a weighted bearings governor 147 of multi-speed hubgear 100 having weighted bearings that are directly pushing the driveplate, according to some embodiments of the present invention. Weightedbearings governor 147 includes a governor planetary gear set 148, forexample having a speed ration of 1:3.9, which is driving a governor base149. Governor base 149 includes guides 150 to hold a drive plate 151.Weighted bearings 152, for example 6 bearings, are positioned betweengovernor base 149 and drive plate 151.

Reference is now made to FIG. 15A which is an illustration of a crosssection of governor 147 at low speed, according to some embodiments ofthe present invention. Reference is also made to FIG. 15B which is anillustration of a cross section of governor 147 at high speed, accordingto some embodiments of the present invention. When governor 147 isturning, weighted bearings 152 are moved outward by centrifugal force asthe speed increases. When weighted bearings 152 are moved outward, theyare pushing drive plate 151, which is held to governor base 149 byguides 150, so drive plate 151 is sliding over guides 150. When thespeed decreases, drive plate 151 is pushed back by return springs 153which are held over guides 150. Optionally, the preload of each ofreturn springs 153 is adjustable.

Optionally, weighted bearings 152 are moving on curves which aredesigned to create discrete positions of drive plate 151 according tothe discrete speeds of multi-speed hub gear 100.

Optionally, the turning speed of hub shell 102 is monitored by anelectronic device, such as a speed sensor, electronically connected tomotor(s) which electronically activates linear actuators 107. Referenceis now made to FIG. 16, which is a schematic illustration of anelectromechanical governor in a multi-speed hub gear, according to someembodiments of the present invention. The electromechanical governor mayconsist of components fixed to axle 101 on an inner chassis 160. Thecomponents may include rechargeable power source(s) 161, electroniccontroller 162 and small electric motor(s) 163, which are connected tohub shell 102 by rotating linear actuator interface(s) 164. Hub shell102 rotates along with magnet(s) 165 embedded in the hub. Sensor(s) onthe controller determine the speed which activates motor(s) 163 to movelinear actuators 107 and change gears.

Reference is now made to FIG. 17, which is a schematic illustration of amulti-speed hub gear, according to some embodiments of the presentinvention. The hub axle 201 is fixed to the bicycle frame. Power isinputted via the chain-driven sprocket 202 and out to the hub shell 203via double one-way bearings 204. The first planet carrier 205 rotatesthe planetary gear sets 206. Each of planetary gear sets 206 rotatesfaster than its predecessor. Between each planetary gear set is alockable one-way bearing 207, which are engaged to hub shell 203 bylinear actuators 208. Linear actuators 208 are pushed and pulled by theexemplary governor 209, which is optionally a centrifugal governor.Governor 209 controls which planetary gear set 206 is engaged to hubshell 203 according to the rotating speed of the hub. The function ofeach one-way bearing 207 is to push hub shell 203 when it is the fastestmoving element and to be able to rotate freely when there are elementsmoving faster than it.

Reference is now made to FIG. 18, which is a flowchart schematicallyrepresenting a method for changing transmission ratio in a multi-speedhub gear, according to some embodiments of the present invention.

First, as shown at 301, turning speed of hub shell 102 is monitored, forexample by counterweights 135 of governor 106 as described above.

Then, as shown at 302, a gear shifter, for example including actuators107, is shifted according to the monitored turning speed of hub shell102. This is done, for example, by a drive plate 128 of governor 106 asdescribed above.

Then, as shown at 303, one of planetary gear sets 109 is engaged to hubshell 102 and, as shown at 304, another of planetary gear sets 109 isdisengaged from hub shell 102. This is done, for example, by lockablegears as described above.

The descriptions of the various embodiments of the present inventionhave been presented for purposes of illustration, but are not intendedto be exhaustive or limited to the embodiments disclosed. Manymodifications and variations will be apparent to those of ordinary skillin the art without departing from the scope and spirit of the describedembodiments. The terminology used herein was chosen to best explain theprinciples of the embodiments, the practical application or technicalimprovement over technologies found in the marketplace, or to enableothers of ordinary skill in the art to understand the embodimentsdisclosed herein.

It is expected that during the life of a patent maturing from thisapplication many relevant multi-speed hub gears will be developed andthe scope of the term hub gear is intended to include all such newtechnologies a priori.

The terms “comprises”, “comprising”, “includes”, “including”, “having”and their conjugates mean “including but not limited to”. This termencompasses the terms “consisting of” and “consisting essentially of”.

The phrase “consisting essentially of” means that the composition ormethod may include additional ingredients and/or steps, but only if theadditional ingredients and/or steps do not materially alter the basicand novel characteristics of the claimed composition or method.

As used herein, the singular form “a”, “an” and “the” include pluralreferences unless the context clearly dictates otherwise. For example,the term “a compound” or “at least one compound” may include a pluralityof compounds, including mixtures thereof.

The word “exemplary” is used herein to mean “serving as an example,instance or illustration”. Any embodiment described as “exemplary” isnot necessarily to be construed as preferred or advantageous over otherembodiments and/or to exclude the incorporation of features from otherembodiments.

The word “optionally” is used herein to mean “is provided in someembodiments and not provided in other embodiments”. Any particularembodiment of the invention may include a plurality of “optional”features unless such features conflict.

Throughout this application, various embodiments of this invention maybe presented in a range format. It should be understood that thedescription in range format is merely for convenience and brevity andshould not be construed as an inflexible limitation on the scope of theinvention. Accordingly, the description of a range should be consideredto have specifically disclosed all the possible subranges as well asindividual numerical values within that range. For example, descriptionof a range such as from 1 to 6 should be considered to have specificallydisclosed subranges such as from 1 to 3, from 1 to 4, from 1 to 5, from2 to 4, from 2 to 6, from 3 to 6 etc., as well as individual numberswithin that range, for example, 1, 2, 3, 4, 5, and 6. This appliesregardless of the breadth of the range.

Whenever a numerical range is indicated herein, it is meant to includeany cited numeral (fractional or integral) within the indicated range.The phrases “ranging/ranges between” a first indicate number and asecond indicate number and “ranging/ranges from” a first indicate number“to” a second indicate number are used herein interchangeably and aremeant to include the first and second indicated numbers and all thefractional and integral numerals therebetween.

It is appreciated that certain features of the invention, which are, forclarity, described in the context of separate embodiments, may also beprovided in combination in a single embodiment. Conversely, variousfeatures of the invention, which are, for brevity, described in thecontext of a single embodiment, may also be provided separately or inany suitable subcombination or as suitable in any other describedembodiment of the invention. Certain features described in the contextof various embodiments are not to be considered essential features ofthose embodiments, unless the embodiment is inoperative without thoseelements.

Although the invention has been described in conjunction with specificembodiments thereof, it is evident that many alternatives, modificationsand variations will be apparent to those skilled in the art.Accordingly, it is intended to embrace all such alternatives,modifications and variations that fall within the spirit and broad scopeof the appended claims.

All publications, patents and patent applications mentioned in thisspecification are herein incorporated in their entirety by referenceinto the specification, to the same extent as if each individualpublication, patent or patent application was specifically andindividually indicated to be incorporated herein by reference. Inaddition, citation or identification of any reference in thisapplication shall not be construed as an admission that such referenceis available as prior art to the present invention. To the extent thatsection headings are used, they should not be construed as necessarilylimiting.

What is claimed is:
 1. A multi-speed hub gear, comprising: an axleadapted to be fixed against rotation; a hub shell; a plurality of gearsets which are mechanically connected to one another, each comprising aring gear rotated by at least one rotating gear mounted on at least onerotating gear carrier, wherein a respective said ring gear of one ofsaid plurality of gear sets is mechanically connected to a respectivesaid at least one rotating gear carrier of another of said plurality ofgear sets such that said plurality of gear sets rotate in conjunction;and a plurality of lockable bearings, each concentrically mountedbetween one of said ring gears and said hub shell to engage anddisengage at least one of said plurality of gear sets by changingposition of at least one of said plurality of lockable bearings betweena locked position where a plurality of rollers of said lockable bearingare locked and an unlocked position where said plurality of rollers arenot locked and are free to rotate.
 2. The multi-speed hub gear of claim1, wherein each of said plurality of gear sets is a planetary gear sethaving a central gear concentrically fixed on said axle and saidrotating gear carrier is mounts said at least one rotating gear torevolve around the center of said central gear.
 3. The multi-speed hubgear of claim 1, further comprising a gear shifter adapted to engagesaid hub shell while disengaging another of said plurality of gear setsfrom said hub shell while disengaging another of said plurality of gearsets from said hub shell.
 4. The multi-speed hub gear of claim 1,wherein said plurality of lockable bearings simultaneously disengage aplanet carrier of one of said plurality of gear sets and engage a planetcarrier of a next one of said plurality of gear sets.
 5. The multi-speedhub gear of claim 1, wherein said plurality of gear sets have the sametransmission ratio.
 6. The multi-speed hub gear of claim 1, wherein saidengaging and disengaging further includes partly disengaging at leastone of said plurality of gear sets so said at least one of saidplurality of gear sets rotates freely at a lower speed relative to saidhub shell.
 7. The multi-speed hub gear of claim 1, wherein each of saidplurality of lockable bearings includes an outer one-way ring and tworing cage plates which includes a plurality of depressions looselyholding said plurality of rollers between said two ring cage plates;wherein said ring cage plates rotate relative to said one-way ring andmoves said plurality of rollers between said locked position where saidplurality of rollers are locked by said outer one-way ring, and saidunlocked position wherein said plurality of rollers are not locked bysaid outer one-way ring.
 8. The multi-speed hub gear of claim 7, whereinat least one of said plurality of lockable bearings partly engage atleast one of said plurality of gear sets when changing position to apartly unlocked position where a plurality of rollers of said lockablebearing are allowed to be locked by said outer one-way ring and saidlockable bearing operates as a one-way bearing.
 9. The multi-speed hubgear of claim 7, wherein each of said plurality of rollers is pushedinto locked position by a spring against angled surface of said outerone-way ring.
 10. The multi-speed hub gear of claim 3, wherein said gearshifter is activated by a governor according to a turning speed of saidhub shell.
 11. The multi-speed hub gear of claim 10, wherein saidgovernor includes a drive plate which pushes said gear shifter whenturning speed of said governor increases.
 12. The multi-speed hub gearof claim 11, wherein said governor includes a return spring which pullssaid drive plate to an initial position when turning speed of saidgovernor decreases.
 13. The multi-speed hub gear of claim 10, whereinsaid governor includes at least one counterweight having an initialposition close to said axle, said at least one counterweight is pushedaway from said axle by centrifugal force applied when turning speed ofsaid governor increases.
 14. The multi-speed hub gear of claim 1,further comprising: a double one-way bearing mechanism which drives saidhub shell.
 15. The multi-speed hub gear of claim 14, wherein said doubleone-way bearing mechanism includes: a first one-way bearing connecting asprocket to a first rotating gear carrier of a first of said pluralityof gear sets so said sprocket drives said first gear set; and a secondone-way bearing connecting said first rotating gear carrier to said hubshell, so sprocket also drives said hub shell.
 16. The multi-speed hubgear of claim 15, wherein at least one of said first one-way bearing andsaid second one-way bearing includes a trapped roller mechanism.
 17. Themulti-speed hub gear of claim 15, wherein at least one of said firstone-way bearing and said second one-way bearing includes a sprag clutchmechanism.
 18. The multi-speed hub gear of claim 15, wherein at leastone of said first one-way bearing and said second one-way bearingincludes a ratchet mechanism.
 19. The multi-speed hub gear of claim 1,used in a wheeled vehicle, wherein said axle is adapted to be fixedagainst rotation in a wheel holder of a wheeled vehicle frame and saidhub shell is mechanically connected to a wheel.
 20. A method of changingtransmission ratio in a multi-speed hub gear, comprising: monitoringturning speed of a hub shell of said multi-speed hub gear relative to anaxle adapted to be fixed against rotation, said hub shell comprising aplurality of gear sets, each of said plurality of gear sets comprises: arotating gear carrier mounting at least one rotating gear; and a ringgear rotated by said at least one rotating gear; shifting a gear shifteraccording to said monitored speed; engaging at least one of a pluralityof gear sets to said hub shell changing a position of a plurality oflockable bearings between a locked position where a plurality of rollersof said lockable bearing are locked and an unlocked position where saidplurality of rollers are not locked and are free to rotate, each one ofsaid plurality of lockable bearings is concentrically mounted betweenone of said ring gears and said hub shell; wherein a respective saidring gear of one of said plurality of gear sets is mechanicallyconnected to a respective said rotating gear carrier of another of saidplurality of gear sets such that said plurality of gear sets rotate inconjunction; and at least partly disengaging another one of saidplurality of gear sets from said hub shell.